Column selection input specification — select

select_spec is used inside teal to create a selectInput that will select columns from a dataset.

Usage

select_spec(
  choices,
  selected = if (inherits(choices, "delayed_data")) NULL else choices[1],
  multiple = length(selected) > 1 || inherits(selected, "all_choices"),
  fixed = FALSE,
  always_selected = NULL,
  ordered = FALSE,
  label = "Select"
)

select_spec.delayed_data(
  choices,
  selected = NULL,
  multiple = length(selected) > 1,
  fixed = FALSE,
  always_selected = NULL,
  ordered = FALSE,
  label = NULL
)

select_spec.default(
  choices,
  selected = choices[1],
  multiple = length(selected) > 1,
  fixed = FALSE,
  always_selected = NULL,
  ordered = FALSE,
  label = NULL
)

Arguments

choices: (character) or (delayed_data) object. Named character vector to define the choices of a shiny selectInput. These have to be columns in the dataset defined in the data_extract_spec where this is called. delayed_data objects can be created via variable_choices or value_choices.
selected: optional (character or NULL or all_choices or delayed_data object). Named character vector to define the selected values of a shiny selectInput. Passing an all_choices() object indicates selecting all possible choices. Defaults to the first value of choices or NULL for delayed data loading.
multiple: (logical) Whether multiple values shall be allowed in the shiny selectInput.
fixed: optional (logical). data_extract_spec specific feature to hide the choices selected in case they are not needed. Setting fixed to TRUE will not allow the user to select columns. It will then lead to a selection of columns in the dataset that is defined by the developer of the app.
always_selected: (character) Additional column names from the data set that should always be selected
ordered: (logical(1)) Flags whether selection order should be tracked.
label: optional (character). Define a label on top of this specific shiny selectInput. The default value is "Select".

Value

A select_spec-S3 class object or delayed_select_spec-S3-class object. It contains all input values. If select_spec, then the function double checks the choices and selected inputs.

Details

To give you some more insights into this function there are several examples. These all start by a data set containing the columns "AGE", "AVAL" and "BMRKR1".

Selection with just one column allowed

select = select_spec(
  choices = c("AVAL", "BMRKR1", "AGE"),
  selected = c("AVAL"),
  multiple = FALSE,
  fixed = FALSE,
  label = "Column"
)

Selection with just multiple columns allowed

select = select_spec(
  choices = c("AVAL", "BMRKR1", "AGE"),
  selected = c("AVAL", "BMRKR1"),
  multiple = TRUE,
  fixed = FALSE,
  label = "Columns"
)

Selection without user access

select = select_spec(
  choices = c("AVAL", "BMRKR1"),
  selected = c("AVAL", "BMRKR1"),
  multiple = TRUE,
  fixed = TRUE,
  label = "Columns"
)

Delayed version

adsl_select <- select_spec(
        label = "Select variable:",
        choices = variable_choices("ADSL", c("BMRKR1", "BMRKR2")),
        selected = "BMRKR1",
        multiple = FALSE,
        fixed = FALSE
      )

all_choices passed to selected

adsl_select <- select_spec(
        label = "Select variable:",
        choices = variable_choices("ADSL", c("BMRKR1", "BMRKR2")),
        selected = all_choices()
      )

Examples

# functional form (subsetting for factor variables only) of select_spec with delayed data loading
select_spec(
  choices = variable_choices("ADSL", subset = function(data) {
    idx <- vapply(data, is.factor, logical(1))
    return(names(data)[idx])
  }),
  # setting first factor variable as default
  selected = variable_choices("ADSL", subset = function(data) {
    idx <- vapply(data, is.factor, logical(1))
    return(names(data)[idx][1])
  }),
  multiple = TRUE
)
#> select_spec with delayed data: ADSL
#> $ choices
#>   variable_choices with delayed data: ADSL
#>   $ data
#>   [1] "ADSL"
#>   $ subset
#>   function(data) {
#>     idx <- vapply(data, is.factor, logical(1))
#>     return(names(data)[idx])
#>   }
#> <environment: 0x562f62dbf7d0>
#>   $ key
#>   NULL
#> $ selected
#>   variable_choices with delayed data: ADSL
#>   $ data
#>   [1] "ADSL"
#>   $ subset
#>   function(data) {
#>     idx <- vapply(data, is.factor, logical(1))
#>     return(names(data)[idx][1])
#>   }
#> <environment: 0x562f62dbf7d0>
#>   $ key
#>   NULL
#> $ multiple
#> [1] TRUE
#> $ fixed
#> [1] FALSE
#> $ always_selected
#> NULL
#> $ ordered
#> [1] FALSE
#> $ label
#> [1] "Select"

# Both below objects are semantically the same
select_spec(choices = variable_choices("ADSL"), selected = variable_choices("ADSL"))
#> select_spec with delayed data: ADSL
#> $ choices
#>   variable_choices with delayed data: ADSL
#>   $ data
#>   [1] "ADSL"
#>   $ subset
#>   NULL
#>   $ key
#>   NULL
#> $ selected
#>   variable_choices with delayed data: ADSL
#>   $ data
#>   [1] "ADSL"
#>   $ subset
#>   NULL
#>   $ key
#>   NULL
#> $ multiple
#> [1] TRUE
#> $ fixed
#> [1] FALSE
#> $ always_selected
#> NULL
#> $ ordered
#> [1] FALSE
#> $ label
#> [1] "Select"
select_spec(choices = variable_choices("ADSL"), selected = all_choices())
#> select_spec with delayed data: ADSL
#> $ choices
#>   variable_choices with delayed data: ADSL
#>   $ data
#>   [1] "ADSL"
#>   $ subset
#>   NULL
#>   $ key
#>   NULL
#> $ selected
#>   variable_choices with delayed data: ADSL
#>   $ data
#>   [1] "ADSL"
#>   $ subset
#>   NULL
#>   $ key
#>   NULL
#> $ multiple
#> [1] TRUE
#> $ fixed
#> [1] FALSE
#> $ always_selected
#> NULL
#> $ ordered
#> [1] FALSE
#> $ label
#> [1] "Select"